Ureaplasma is a genus of tiny bacteria belonging to the Mycoplasma family. These organisms lack a rigid cell wall, which has implications for their treatment. They commonly colonize the genitourinary tract in both men and women, often existing as a harmless part of the natural microbiome. While many individuals carry Ureaplasma without symptoms, the bacteria can become opportunistic and cause infection. Clarifying the ways this organism is transmitted is important because it is not exclusively passed through sexual contact.
Primary Mode of Ureaplasma Transmission
Sexual contact is the most frequent and primary route through which Ureaplasma is acquired by adults. The bacteria are transferred when bodily fluids are exchanged during unprotected sexual activity, including vaginal, anal, and oral sex. Because of this common route, Ureaplasma is often categorized by clinicians as a non-gonococcal, non-chlamydial sexually transmitted infection (STI). The prevalence of colonization is significantly higher in sexually active adults compared to those who are sexually inactive.
Non-Sexual Transmission Routes
The most well-established non-sexual pathway is vertical transmission, which occurs from a pregnant person to their offspring. This transmission can happen in three distinct ways: in utero, during delivery, and, rarely, postnatally. In utero transmission occurs when the bacteria ascend from the lower genital tract into the amniotic fluid or, less commonly, through the placenta. Perinatal exposure takes place as the infant passes through a birth canal colonized with Ureaplasma. Transmission through casual contact, such as from shared towels or toilet seats, is generally considered negligible or non-existent in healthy adults.
The vertical transmission rate from a colonized mother to her newborn ranges widely, often affecting between 18% and 55% of full-term infants. Newborns, particularly those with very low birth weight, have a higher rate of colonization, with the transmission rate approaching 90% in infants weighing less than 1 kilogram.
Associated Health Conditions and Symptoms
Once established, Ureaplasma can become clinically relevant by contributing to health complications, particularly when overgrowth occurs.
Conditions in Adults
In men, the bacteria are a recognized cause of non-gonococcal urethritis (NGU), characterized by inflammation of the urethra. This condition can present with symptoms like burning during urination, a thin discharge from the penis, and discomfort. For women, Ureaplasma overgrowth has been associated with cervicitis (inflammation of the cervix) and pelvic inflammatory disease (PID). PID is a serious infection of the upper reproductive organs that can cause lower abdominal pain and lead to infertility. The bacteria have also been linked to bacterial vaginosis.
Risks During Pregnancy and for Neonates
In pregnant individuals, colonization is associated with an increased risk of adverse outcomes, including premature rupture of membranes and preterm birth. When vertical transmission occurs, the consequences for the newborn can be severe. Ureaplasma infection in neonates may lead to pneumonia, meningitis, and sepsis. In premature infants, the infection can cause lung inflammation that contributes to the development of chronic lung disease, specifically bronchopulmonary dysplasia.
Diagnosis and Treatment Protocols
Diagnosis of Ureaplasma infection is performed by identifying the organism in clinical samples, such as a swab of the urethra or cervix, or a first-void urine sample. Molecular techniques, such as Polymerase Chain Reaction (PCR) testing, are commonly used for their precision in detecting the bacteria’s genetic material. Culture methods can also be employed, though Ureaplasma requires specialized media for growth.
The absence of a cell wall means Ureaplasma is naturally resistant to antibiotics like penicillins and cephalosporins, which target cell wall synthesis. Treatment protocols rely on specific types of antibiotics that work through different mechanisms. The most common treatments are tetracyclines, such as doxycycline, and macrolides, including azithromycin. A typical course involves a seven-day regimen of doxycycline for non-pregnant adults. Azithromycin may be used as an alternative, often administered as a single, large dose or a shorter course. It is recommended that sexual partners of an infected individual also be evaluated and treated simultaneously to prevent re-infection.